Solvent refining



Patented Oct.4,1938 g V 2,131,999

' I 1 21s1,999 OLVENT RE G p LouisA; Clarke, Fishkill;..-N. Y.,' assignor?to1:-'lhe Texas Company, New York, N. Y., a corporation-of.Delawarer r no'pr wing, A plicants Marclr 2'1,193f7,"Serial v --:5-;o1aims. (o1. Isle-1st v This invention relates to jrefiningfhydrocar- 'phases are-removed and separately subjected to bon oil, and more particularly'torefining mineral distillation during which the motor fuel constitoil by solvent extraction." I V I uents, being thernore volatile, are distilledfrom The invention contemplatesthetreatment'of "the'solventi" "if; t 5 hydrocarbon oil to separate th'e' oil into fractions Inthe case oflubr'icating 'oilextraction, where 5 of difiering'characteristics by extraction with a "constituent s of'the oil undergoing treatment may solvent selected from the group consisting of "boil at a ternperature not greatly diiferent from amino and nitro diphenyl. Am'inolliphenyl is; a theboilingtemp'eratureof th s ve t s p a n compound having the. chemical formula? y be effected by jectin t e Ireof Oil M and solvent toa washing'or displacement treat- NH2 C6H4 C6H5 ment, using a liquid medium which, when incorhi njtro djpheny] is a compound having the porated in the mixture, renders the oil and solchemical formula: NO2C6H4C6H5. Vent Substantially immiscible- I have discovered that these compounds, in- The following es s ate he app ca- 16 cluding the ortho meta and para form of each tion Of this invention to the treatment of motor are adapted t t extraction of hydrocarbon 11 fuel stock for the purpose of separating therefrom and particularly mineral 01151 These compounds a fraction which is rich in'constituents having a are suitable, for example, for the extraction of high anti-knock value- The Stock used in these motor fuel stock or naphtha for the purpose of examples comprises a Straight run gasoline P 20 separating therefrom fractions rich in constitduced by distillation from East Texas Orv-(1% 2o uents having high anti-knock value. They are This Straight run gasoline had the following also suitable for the solvent extraction of lubritests:

eating oil for the purpose of separating the oil Gravity P. I 5437 into fractions respectively rich in paraffinoid and Initial boiling point o 170 non-paramno-id constituents. These compounds Fifty per cent boiling point o 268 25 exert preferential solvent action upon the rela- End boiling point 346 titvely non-paraffinoid or low viscosity index Octane number (QRRHM') 53 constituents of the oil, and thus provide a means of refining lubricating oil stock for the produc- A sample of this gasoline is subjected to contion of oil having a relatively high viscosity index. tinuous countercurrent contact with ortho nitro 30 These compounds are particularly suitable for diphenyl,-using two parts by volume of solvent the extraction of gasoline or naphtha since they o One p t y Volume of gasoline When the have a relatively high boiling point and, theretraction is carried out at around a temperature fore, make it possible to separate the solvent from of 90 F., separation into extract and raffinate the gasoline or naphtha constituents with facilphases occurs. The extract phase comprises the 35 ity. As indicated below, these compounds have relatively high anti-knock constituents o t e boiling points of around 300 C. and above at atgasoline dissolved in the main body of the solmospheric pressure, which is substantially above vent, while the raflinate phase comprises the relathe boiling point of the highest boiling constittively insoluble p t of he asoli e mixed uents usually present in naphtha or motor fuel with a small amount of the solvent. 40 stock, the end boiling point of which is around These phases are removed and separately sub- 200 to 250 C. jected to distillation for the purpose of stripping Boiling point 0 C. therefrom the gasoline constituents. Ortho amino diphenyl 299 The extract portion removed from the extract Meta amino diphenyl *254 phase will amount to about 25% of the original 45 Para amino diphenyl 302 straight run gasoline and will have an octane Ortho nitro diphenyl 320 number of about 66 to 70 as determined by the Para nitro diphenyl 340 Cooperative Fuel Research Method.

*Under pressure Treatment of another sample of this same gas- 50 oline with para amino diphenyl, using the same 50 Accordingly, when extracting motor fuel stock solvent ratio, and at a temperature of F. with these compounds, the extraction is made in produces an extract phase which contains an the usual manner involving either continuous or extract comprising 20% of the raw gasoline and step countercurrent contact. Separation into also having an octane number of 66 to 70, de-

35 extract and raffinate phases results. These termined by the same method. 55

solvents of my invention may be carried out in either continuous or step countercurrent operation. If desired, the extraction may be carried out in a batch treating operation. Extraction may be efiected in a countercurrent tower type of apparatus in which the solvent is introduced near the top, of} a 'packed vertical, .towerfiwhile the oil to be treated is introduced near the" bottom of the tower.

been specifically mentioned, it is contemplated that these may be variedg'depending'upon .the

nature of the stock undergoing treatment as'well as upon the degree of extraction desired.

Obviously, many modifications and variations of the invention, as hereinbefore set forth,-;may

be made without departing from the spirit and scope thereof, and therefore only sucli limitations should be imposed as are indicated in the appended claims. V I Y IcIaimI 7 4 p 1. In the refining of'hy'drocarbon oil to separate the oil into fractions respectively rich in parafiinoid and non-paraffinoid constituents, the

method comprising extractingthe 'oil with a solvent selected from the group consisting ofnitroand amino vdephenyLforming anex-tract phase ge comprising nonparafiinoid constituents dissolved in the bulk of the solvent and a raifinate phase comprising paraffinoid constituents mixed with a small portion of the solvent, separating the 2. The method according to claim 1 in which the solvent comprises ortho nitro diphenyl.

3. The method according to motor fuel from a motor fuelstock containing While in the foregoing examples, certain sol-i constituents of low and high anti-knock value 'vent ratios and extraction temperatures have comprising extracting said stock with a solvent selected from the group consisting ofnitro and iamino ,diphenyl, forming an extract phase comprising high anti-knock constituents of the stock dissolved'in the main body of the solvent and a raflinate phase, comprising constituents of 10W "anti knock'value; separating the two phases; and

removing the solvent therefrom.

BXThe-methOd of solvent refining hydrocarbon 7 oil to.s eparat e,the oil into fractions respectively rich in paraffinoid, and vnon-paraftinoid constituents "comprising extracting the oil with nitro diphenyl, forming an extract phase comprising non-parafiinoidconstituents dissolved in the bulk ofthe solvent and a portion of the solvent, and s'eparatingthe two phases. V

LQUIS AKCLARKE;

two phases, and removing the solvent therefrom.

claim l'in which the solvent comprises para: amino 'diphenyl.

Themethod of producing a high anti-knock I V rafiinate phase comprising parafiinoidconstituents mixed with a small pro- 

